/** 作战地图图下明细表（由 buckets 生成）。 */

export type LevBucket = {
  label: string;
  n: number;
  mean: number | null;
  pct_ge_min: number | null;
  days?: number;
  days_hit?: number;
  pct_days_hit?: number | null;
};

export type MoveBucket = {
  label: string;
  n: number;
  mean_abs: number | null;
  mean_signed: number | null;
  days?: number;
};

export type LevTableRow = {
  label: string;
  days: number;
  daysHit: number;
  pct: number | null;
  mean: number | null;
  n: number;
};

export type MoveTableRow = {
  label: string;
  days: number;
  n: number;
  meanAbs: number | null;
  meanSigned: number | null;
};

export type SummaryTable<T> =
  | { kind: "empty"; message: string }
  | { kind: "table"; note?: string; rows: T[] };

function fmtPct(p: number): string {
  return `${Math.round(p * 100)}%`;
}

function fmtNum(n: number, d = 1): string {
  return n.toFixed(d);
}

function withData<T extends { n: number }>(buckets: T[]): T[] {
  return buckets.filter((b) => b.n > 0);
}

/** 达标概率优先用按日口径 pct_days_hit，兼容旧数据回退到样本口径。 */
function hitRate(b: LevBucket): number | null {
  if (b.pct_days_hit != null) return b.pct_days_hit;
  return b.pct_ge_min;
}

function dayCount(b: LevBucket): number {
  if (typeof b.days === "number") return b.days;
  return b.n > 0 ? 1 : 0;
}

function daysHitCount(b: LevBucket, minLeverage: number): number {
  if (typeof b.days_hit === "number") return b.days_hit;
  if (b.mean != null && b.mean >= minLeverage && b.n > 0) return 1;
  return 0;
}

/** 上图杠杆明细表 */
export function leverageSummaryTable(
  range: "day" | "week" | "month",
  buckets: LevBucket[],
  minLeverage: number
): SummaryTable<LevTableRow> {
  const active = withData(buckets);
  if (!active.length) {
    return {
      kind: "empty",
      message: "所选范围内暂无杠杆样本，采集后将显示各时段分布。",
    };
  }

  const rows: LevTableRow[] = [...active]
    .map((b) => ({
      label: b.label,
      days: dayCount(b),
      daysHit: daysHitCount(b, minLeverage),
      pct: hitRate(b),
      mean: b.mean,
      n: b.n,
    }))
    .sort((a, b) => {
      const dp = (b.pct ?? -1) - (a.pct ?? -1);
      if (dp !== 0) return dp;
      const dh = b.daysHit - a.daysHit;
      if (dh !== 0) return dh;
      return (b.mean ?? 0) - (a.mean ?? 0);
    });

  const windowName = range === "day" ? "今日" : range === "week" ? "本周" : "本月";
  const note =
    range === "day"
      ? `${windowName}各时段明细（达标 = 该时段均值 ≥ ${minLeverage}）`
      : `${windowName}各时段明细（达标 = 当日该时段均值 ≥ ${minLeverage}；概率 = 达标天数 ÷ 一共几天）`;

  return { kind: "table", note, rows };
}

/** 下图波动明细表 */
export function moveSummaryTable(
  range: "day" | "week" | "month",
  buckets: MoveBucket[],
  opts: {
    pendingExpiry?: boolean;
    pendingCount?: number;
    mode: "abs" | "signed";
    apiMessage?: string | null;
  }
): SummaryTable<MoveTableRow> {
  if (opts.pendingExpiry) {
    const extra = opts.apiMessage ? ` ${opts.apiMessage}` : "";
    return {
      kind: "empty",
      message:
        `未到期，暂无法统计时段→到期波动；结算后将按日/周/月给出各钟点明细。${extra}`.trim(),
    };
  }

  const active = withData(buckets).filter((b) =>
    opts.mode === "abs" ? b.mean_abs != null : b.mean_signed != null
  );
  if (!active.length) {
    return { kind: "empty", message: "所选范围内暂无已结算波动样本。" };
  }

  const windowName =
    range === "day" ? "今日" : range === "week" ? "本周" : "本月";

  const rows: MoveTableRow[] = [...active]
    .map((b) => ({
      label: b.label,
      days: typeof b.days === "number" ? b.days : b.n > 0 ? 1 : 0,
      n: b.n,
      meanAbs: b.mean_abs,
      meanSigned: b.mean_signed,
    }))
    .sort((a, b) => {
      if (opts.mode === "abs") {
        return Math.abs(b.meanAbs ?? 0) - Math.abs(a.meanAbs ?? 0);
      }
      return Math.abs(b.meanSigned ?? 0) - Math.abs(a.meanSigned ?? 0);
    });

  const note =
    opts.mode === "abs"
      ? `${windowName}各时段→到期绝对波动明细`
      : `${windowName}各时段→到期带符号波动明细`;

  return { kind: "table", note, rows };
}

/** @deprecated 保留短句接口给旧调用；新 UI 用表格。 */
export function leverageSummary(
  range: "day" | "week" | "month",
  buckets: LevBucket[],
  minLeverage: number
): string {
  const t = leverageSummaryTable(range, buckets, minLeverage);
  if (t.kind === "empty") return t.message;
  const top = t.rows.slice(0, 5);
  const list = top
    .map(
      (r) =>
        `${r.label}（一共 ${r.days} 天，达标 ${r.daysHit} 天${
          r.pct != null ? `，${fmtPct(r.pct)}` : ""
        }）`
    )
    .join("、");
  return `${t.note}：${list}。`;
}

export function moveSummary(
  range: "day" | "week" | "month",
  buckets: MoveBucket[],
  opts: {
    pendingExpiry?: boolean;
    pendingCount?: number;
    mode: "abs" | "signed";
    apiMessage?: string | null;
  }
): string {
  const t = moveSummaryTable(range, buckets, opts);
  if (t.kind === "empty") return t.message;
  const top = t.rows.slice(0, 5);
  if (opts.mode === "abs") {
    return `${t.note}：${top
      .map((r) => `${r.label}（${fmtNum(r.meanAbs ?? 0, 2)}，${r.days} 天）`)
      .join("、")}。`;
  }
  return `${t.note}：${top
    .map((r) => {
      const v = r.meanSigned ?? 0;
      return `${r.label}（${fmtNum(v, 2)}，${r.days} 天）`;
    })
    .join("、")}。`;
}

export { fmtPct, fmtNum };